#include<stdio.h>

void cycle() 
{
	int i = 0;
	int m = 0;
	printf("Enter a number: ");
	scanf_s("%d", &m);
	for (i = 2; i <= m / 2; i++) 
    {
		if (m % i == 0) break;
	}
	if (i > m / 2 && m != 1) 
    {
		printf("%d is a prime number! \n", m);
	}
	else
     {
		printf("No!\n");
	}
}

int main()
 {
	cycle();
	return 0;
}